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Updated: Jun 3, 2026
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Assembly of Cell Mimicking Supported and Suspended Lipid Bilayer Models for the Study of Molecular Interactions
Published on: August 3, 2021
Bilayers connected by threadlike micelles in amphiphilic mixtures: a self-consistent field theory study
Martin J Greenall1, Gerhard Gompper
1Theoretical Soft Matter and Biophysics, Institute for Complex Systems, Forschungszentrum Jülich, 52425 Jülich, Germany.
Langmuir : the ACS Journal of Surfaces and Colloids
|March 9, 2011
Summary
Binary amphiphile mixtures form complex structures like connected vesicles. Adding sphere-forming lipids to lamellar systems stabilizes threadlike micelles, but excess destabilizes the structure.
Area of Science:
- Physical Chemistry
- Materials Science
- Soft Matter Physics
Background:
- Amphiphilic molecules self-assemble into diverse structures in solution.
- Mixtures of amphiphiles with different aggregate curvatures can lead to complex co-assembly.
- Lipid mixtures forming lamellar phases and spherical micelles provide a model system for studying co-assembly.
Purpose of the Study:
- To investigate the self-assembly of binary amphiphile mixtures, specifically lipid mixtures forming lamellar and spherical aggregates.
- To understand the formation and stability of connected vesicle structures formed by threadlike micelles.
- To elucidate the role of sphere-forming lipids in modulating the self-assembly of lamellar-forming lipids.
Main Methods:
- Utilized self-consistent field theory (SCFT), a coarse-grained computational model.
- Simulated binary mixtures of amphiphiles with differing curvature preferences.
- Analyzed the free energy, composition, and curvature coupling within self-assembled structures.
Main Results:
- Addition of sphere-forming lipids lowers the free energy of cylindrical micelles, promoting their formation.
- A coupling between composition and curvature was observed, with amphiphiles transferring to the threadlike micelle.
- Amphiphiles segregated within the structure, with sphere-formers concentrating in the thread.
- Excess sphere-forming lipids destabilized the junctions connecting bilayers to micelles, leading to structural breakdown.
Conclusions:
- Binary amphiphile mixtures offer tunable pathways to complex self-assembled structures.
- The length of the hydrophilic block of sphere-forming amphiphiles influences amphiphile segregation and structural stability.
- SCFT provides a powerful tool for predicting and understanding self-assembly in complex amphiphile systems.
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